For most people, the biggest decisions about holiday shows are which to attend and where to sit. But for parents of children with autism, the question is whether their child will enjoy or be disturbed by the experience.

In recent years, the joy of “The Nutcracker,” “The Polar Express” and other holiday classics has become more accessible thanks to sensory-friendly and autism-friendly performances. In an environment modified to avoid extremes, low house lights stay on, loud sounds are muted, strobe lights eliminated and audience silence and stillness are not expected.

“It’s such an important thing, to make this show comfortable for everyone,” said choreographer and director Tony Williams, who has offered an autism-friendly performance of “The Urban Nutcracker” since 2014. “It means the whole family can enjoy it together.”

At autism-friendly shows, parents know that they and their children will not receive unwelcome stares if they make noise, move around in their seats, or get up to leave the performance space. Throughout the performance, people can take a break to go to a quiet area staffed with volunteer helpers, and re-enter at any time.

This inclusiveness is particularly appreciated during the holidays, when families often have a tradition of going to a holiday show.

Williams, whose Tony Williams Dance Center in Jamaica Plain has produced “The Urban Nutcracker” for 17 years, decided to offer an autism-friendly show at the suggestion of the mother of his student, who had a sibling with autism.

“The first year, we took a chance because we still had to pay our costs, but knew it wouldn’t be a full house,” Williams said. “So we were pleased with how many people came.”

From 400 the first year, the number grew to 600 last year, which included families without an autistic member but who liked the flexibility of the performance.

Autism-friendly performances are still relatively new and rare, despite the large number of children on the autism spectrum. Autistic people have widely varied symptoms that to some degree reflect problems with social interactions and communication. According to a Centers for Disease Control and Prevention report in 2014, one in 68 U.S. children has an autism-spectrum disorder.

The Autism Theatre Initiative of New York collaborated with producers to stage the first autism-friendly Broadway show in 2011, “The Lion King,” which was followed by autism-friendly performances of “Aladdin” and “Matilda.” When “The Lion King” came to the Opera House with Broadway in Boston in 2014, an autism-friendly performance was offered.

On the sensory-friendly car of the Scituate North Polar Express, the 65 tickets sell out quickly. During the ride, the experience is modified to lower the volume of the music and story reading and to provide more room for children to move around. The visiting elves and Santa understand ways to respond to some of the behaviors and needs of children with autism.

“My mantra is that children with autism want to do what other children are doing, but they just need support to do that,” said Tracy Johnson, president of CORSE (Scituate Community of Resources for Special Ed) who has a son with autism. “Many parents told me that the train is just too loud or they’re worried their child will have a tantrum and ruin it for other kids. So we have a non-judgmental zone where they can have a good time.”

While the Boston Ballet has no sensory-friendly performances, it is offering its first “All-Access Nutcracker” performance designed for people with hearing and vision limitations. In addition to ASL interpretation, hearing-impaired people can use equipment that enhances the audio; vision-impaired people can use large print programs and headsets to hear a description of the story, costumes and movement in real time. All-Access seats will be reserved in the left orchestra section, at a single price to ensure affordability. Ticket holders also can visit the Boston Ballet studios two days before the performance to touch costumes and props.

In this original production, tap, hip-hop and ballet dancers bring an inventive interpretation to Tchaikovsky and Duke Ellington. New for this year, the Nutcracker and cast visit the duckling sculptures in the Public Garden, Chinatown and other Boston scenes.

“Charlotte’s Web,” 2 p.m. Dec. 29, American Repertory Theater, 64 Brattle St., Cambridge. Tickets can be purchased at the box office or by calling 617-547-8300. For information, go to www.americanrepertorytheater.org/page/sensory-friendly-performances.

“Charlotte’s Web” brings to life the classic book by E.B. White about an extraordinary spider who saves her friend, Wilbur the pig.

“Miracle on 34th Street,” 11 a.m. Dec. 3, Town Hall, 11 Town House Road, Weston. For information, go to www.westonfriendly.org.

An abbreviated version of the play based on the classic film is performed with cabaret-style seating and quiet break areas.

“North Pole Express,” 12:30 p.m. Dec. 10, Greenbush Commuter Rail Station, 247 Old Driftway, Scituate. Tickets are $28. The train is sold out: reservations accepted for 2018 in early October. For information, go to www.scituatenorthpoleexpress.com. One car is designated as sensory-friendly on this train ride, which replicates the journey to the North Pole from the story “The Polar Express.” Children hear a reading of the book, sing carols, enjoy milk and cookies, and receive a gift from Santa and Mrs. Claus.

Jody Feinberg is at jfeinberg@ledger.com or follow her on Twitter @JodyF_Ledger.